Often, reliability systems suffer shocks from external stress factors,
stressing the system at random. These random shocks may have
non-ignorable effects on the reliability of the system. In this paper, we provide sufficient
and necessary conditions on components' lifetimes and their survival
probabilities from random shocks for comparing the lifetimes of two parallel
systems by means of usual stochastic and reversed hazard rate orders, when the matrix of parameters changes to another matrix in a mathematical sense.
The results developed in this paper generalize some known results in the literature.